Apparatus for folding over ends of paper tubes



L. D. PIERCE I 2,163,805

APPARATUS FOR FOLDING OVER ENDS OF PAPER TUBES June 27, 1939.

Filed April 6, 1957 VENTOR. BY W j MV ATTORNEY 5 Patented June 27, 1939 UNITED STATES APPARATUS FOR FOLDING OVER ENDS OF PAPER TUBES Lee D. Pierce, Fulton, N. Y.

Application April 6, 1937, Serial No. 135,299

Claims.

This invention relates to a device for spinning or folding over the end of a paper cylinder, and has as an object a device of the type referred to embodying a particularly economical and efii- 5 cient construction by which the length of the over-turned portion is accurately controlled throughout the circumference of the paper cylinder, and the over-turned portion is compressed and ironed to the required form and within extremely close dimensions.

The invention consists in the novel features and in the combinations and constructions hereinaiter set forth and claimed.

In describing this invention, reference is had to r the accompanying drawing in which like characters designate corresponding parts in all the views.

Figure 1 is a vertical, sectional view of a device embodying my invention illustrating the relative position of the parts at the completion of the folding operation.

Figure 2 is a fragmentary, plan view of the base member.

Figure 3 is an inverted plan view of the spinning head.

Figure 4 is a fragmentary, vertical, sectional view illustrating the relative position of the parts to the folding operation.

Figure 5 is a fragmentary, vertical, sectional view illustrating a modified form of construction operable to turn the infolded portion of the paper cylinder inwardly.

The invention comprises generally, a base member formed to support the paper cylinder with one end portion thereof extending outwardly from the base, and a spinner head movable axially toward and from the base and being operable to fold over the projecting portion of the cylinder.

The invention further includes stop means to limit the length of the over-folded portion of the cylinder, and stop means to limit the axial movement of the spinning head toward the base, said stop means being so arranged or positioned relatively as to effect a compression of the overturned end of the cylinder and an ironing thereof to accurately control the dimensions of the overturned portion.

In the construction of .certain articles from paper and like material, cylinders or tubes are employed and. the ends folded or spun over as an initial step in theformation of the article, such for example as slip covers in which the cylinder'or tubular portion comprises the depending annular flange of the slip cover, the construction 55 of which is completed by the attachment of a disccidal portion to the tube or cylinder, and this union of the cylinder and discoidal portion is effected through means of the over-folded end of the cylinder. In certain of these constructions, it is essential that the over-folded portions ofthe respective parts be of uniform accurate dimensions, and this requirement is difficult to obtain with the ordinary conventional mechanisms and methods now used for spinning or folding over the ends of tubes.

In the construction here shown, the base I0 is of circular formation provided with radially extending lugs l I by which the base is attached to the paper converting machine which is equipped with a rotating spindle l3 arranged vertically and in axial alinement with the base. The base H] is formed with a peripheral shoulder M, the upper portion of the base being of such diameter as toslidably receive the paper tube or cylinder IS with the lower edge thereof supported on the shoulder l4. When it is desired to spin or fold the projecting end of the cylinder l5 outwardly, a sleeve 16 is employed which encircles the cylindrical portion of the base, and the lower portion of the paper cylinder I5, and is formed at its. upper end with an annular surface or flange H, the function of which will be referred to hereinafter. The folding or spinning is accomplished by a spinning head 20 threading on the end of the spindle l3 and provided with an annular groove 2i on its lower face confronting the upper surface of the base ll].

A plurality of pins 22 are arranged in radial formation inthe head 20 and are formed on one side with circular slots 24. The pins 22 are held in the head 20 by means of set screws 25. The construction of the spinning head 20 is more or less conventional and forms per se no part of this invention. It will be understood that the rotary spindle I3 is movable axially toward and from the top surface of the base l0, and during such movement the projecting end portion of the paper cylinder I5 enters the groove H of the spinning head and the pins 22 cause the end of the cylinder or tube to fold outwardly as the spindle l3 and head 20 are moved axiallytoward the base It; in the'conventional manner. During this operation the sleeve l6 holds the cylinder 95 from rotation. This operation continues until the over-folded portion 26 contacts the flange ll of the sleeve [6 which prevents further overfolding of the tube or cylinder, and at which time the inner surface 28 of the spinning head approaches the top surface of the base Ill.

The relative arrangement and construction of the spinning head, base In and flange ll of sleeve [6, is such that there is a slight axial movement of the spinning head 20 toward the base Hi after the edge of the over-folded portion 26 seats against the flange l I. This further axial movement results in a compression and ironing out of the over-folded end portion of the cylinder, the length of which is definitely limited by the flange ll. In practice, the desired length of the cylinder from the lower end thereof to the edge of the over-folded portion and the length of the over-folded portion is determined, and the blank tube or cylinder is cut in lengths slightly greater than that required so that the edge of the over-turned portion 26 is compressed against the flange l1 and the upper end of the cylinder ironed smooth and compressed by the action of the spinning head. The thickness of the overturned portion of the cylinder is also controlled by the width of the groove 2|.

Where it is desired to fold the end of the tube inwardly, the base It may be formed with an annular flange 30 which acts as a stop for the over-turned portion of the tube, and a sleeve 3| employed as a stop for the spinning head 29. The sleeve 3| is similar to the sleeve I6, except that it is not necessary to provide the upper edge of the same with a flange corresponding to the flange H. In this instance, the sleeve 3| functions to properly hold the paper tube or cylinder, and to act as a stop for the spinning head, and the relative dimensions and positions of the flange 30, sleeve 3|, and length of the blank tube are such as to effect the folding over of the end of the tube against the flange 30 just prior to the contact of the spinning head with the sleeve 3| to effect the same result as produced by the structure previously described in connection with the outfolding of the tube.

It will be understood by those familiar with the art that the paper tubes are usually made in long lengths, placed on a mandrel, and. severed into shorter lengths of proper length by a plurality of properly spaced apart knives. That is, it is a comparatively simple matter to cut the blank tubes or cylinders to accurate lengths, and when these are used in connection with the structure described, the over-folded portion of the tube is accurately formed and held to close dimensions in volume production, with the result that the processed tubes or cylinders may be conveniently assembled with other similar paper articles.

What I claim is:

1. A device for folding over the end of a paper cylinder, the combination of a base formed to support said cylinder with one end thereof extending outwardly from the base, of a rotary spinning head movable axially toward and from. the base and being operable to turn over the extending end of the cylinder, a sleeve encircling the base and a portion of said cylinder with the end of the sleeve acting as a stop for the over-turned portion of the cylinder, said base and head having coacting surfaces located within the spinning area to limit axial movement of the head toward the base, the end of said sleeve and said surfaces being arranged relatively, whereby the spinning head presses the over-turned portion of the cylinder against the end of the sleeve and eifects an ironing of said over-turned portion.

2. A device for folding over the end of a paper cylinder, the combination of a base, a rotary spinning head movable axially toward and from said base, said base being formed to support said cylinder with one end thereof extending outwardly from the base toward the spinning head, said spinning head being operable upon engagement with the outwardly extending portion of the cylinder to fold said portion over upon itself with the overlapped portion extending parallel to the cylinder, a stop rigidly carried by the base to limit the length of the overfolded portion of the cylinder, and a stop rigidly carried by the base to limit the axial movement of the spinning head toward the base, said second stop being arranged relative to said first stop to permit limited axial movement of the spinning head toward the base after said overfolded portion of the cylinder engages said first stop.

3. A device for folding over the end of a paper cylinder, the combination of a base, a rotary spin ning head movable axially toward and from said base, said base being formed to support said cylinder with one end thereof extending outwardly from the base toward the spinning head, said spinning head being operable upon engagement with the outwardly extending portion of the cylinder to fold said portion over upon itself with the over-folded portion extending parallel to the cylinder, a ring member encircling the base, said base being provided with a stop member, one of said members being arranged to engage and to limit the length of the overfolded portion of the cylinder, and the other to limit the axial movement of the spinning member toward the base subsequent to engagement of the over-folded portion by said member.

4. A device for folding over the end of a paper cylinder, the combination of a base, a rotary spinning head movable axially toward and from said base, said base being formed to support said cylinder with one end thereof extending outwardly from the base toward the spinning head, said spinning head being operable upon engagement with the outwardly extending portion of the cylinder to fold said portion over upon itself with the over-folded portion extending parallel to the cylinder, a ring member rigidly carried by the base and encircling the same with the upper edge of said ring member acting as a stop to limit the length of the overfolded portion of the cylinder, a stop member'rigidly carried by the base to permit slight axial movement of the spinning head toward the base subsequent to engagement of the over-folded portion with said ring member.

5. A device for folding over the end of a paper cylinder, the combination of a base, a rotary spinning head movable axially toward and from said base, said base being formed to support said cylinder with one end thereof extending outward- 1y from the base toward the spinning head, said spinning head being operable upon engagement with the outwardly extending portion of the cylinder to fold said portion over upon itself, a ring member rigidly supported by the base and encircling the same with the upper edge of the ring member acting as a stop tolimit the axial movement of the spinning head toward the base, a stop member carried by the base and being operable to limit the length of the over-folded portion of the cylinder, and said stop members being cooperable to effect an ironing of the overfolded portion of the cylinder.

LEE D. PIERCE. 

